Study Links Sterol-Inhibiting Drugs to Autism Risk

Summary: A massive nationwide study uncovered a significant link between common medications and Autism Spectrum Disorder (ASD). The research analyzed over 6 million births—nearly one-third of all U.S. births over the last decade.

The findings suggest that medications that unintentionally inhibit the cholesterol (sterol) synthesis pathway in the womb are associated with a nearly 50% increase in autism risk for offspring.

Key Findings

  • 1.47-Fold Higher Risk: Mothers prescribed at least one SBIM during pregnancy had a 47% higher risk of having a child with ASD.
  • Dose-Dependent Increase: The risk skyrocketed with multiple medications. Two or three SBIMs increased the risk further, while exposure to four or more simultaneously resulted in a 2.33-fold (133%) increase in ASD risk.
  • Rising Exposure: Use of these medications during pregnancy has nearly quadrupled, rising from 4.3% in 2014 to 16.8% in 2023.
  • Cohort Scale: Of the nearly 200,000 children diagnosed with ASD in the study, 14.2% had been exposed to these medications in the womb.

Source: UNMC

A landmark study led by researchers at the University of Nebraska Medical Center (UNMC) and published in Molecular Psychiatry has identified a significant association between prenatal prescription of commonly utilized medications and the risk of autism spectrum disorder (ASD) in children. 

Analyzing 6.14 million maternal-child health records from the Epic Cosmos database —representing nearly one-third of all U.S. births between 2014 and 2023 — the team found that prescription of medications known to inhibit the cholesterol synthesis pathway were consistently associated with higher rates of ASD in offspring. 

While previous studies grouped medications by their indications, the UNMC team grouped prescribed medications together based on common effects and side effects on sterol biosynthesis. 

These sterol biosynthesis–inhibiting medications (SBIMs) include certain antidepressants, antipsychotics, anxiolytics, beta-blockers and statins. These are the generic names of the 14 medications studied: aripiprazole, atorvastatin, bupropion, buspirone, fluoxetine, haloperidol, metoprolol, nebivolol, pravastatin, propranolol, rosuvastatin, sertraline, simvastatin and trazodone. Many of these are among the most commonly prescribed medications in the United States, accounting for more than 400 million annual prescriptions. 

Key findings 

  • Mothers prescribed at least one SBIM during pregnancy had a 1.47-fold higher risk of having a child diagnosed with ASD. Risk increased in a dose-dependent manner. For each additional SBIM co-prescribed, there was a 1.33 times increased risk of ASD, reaching 2.33-fold risk when four or more SBIMs were prescribed simultaneously. 
  • Among the 196,447 children diagnosed with ASD in the cohort, 14.2% had prenatal SBIM exposure. 
  • Use of SBIMs during pregnancy increased sharply over time, rising from 4.3% of pregnancies in 2014 to 16.8% in 2023. 

Why sterol biosynthesis matters 

Cholesterol is essential for fetal development, especially for the brain, the most cholesterol-rich organ. The fetal brain begins producing its own sterols around 19–20 weeks of gestation. 

Genetic disruptions in this pathway are known to cause severe developmental syndromes such as Smith-Lemli-Opitz syndrome (SLOS), in which up to 75% of children meet criteria for ASD. Many widely used medications can unintentionally interfere with this pathway. 

This study is the first nationwide investigation to evaluate the neurodevelopmental outcomes associated with prenatal exposure to this group of medications. 

A public health signal requiring attention 

“Our findings do not suggest that these medications are unsafe for adults,” said senior author Karoly Mirnics, MD, PhD, dean and director of the UNMC Munroe-Meyer Institute. “But they raise important questions about their use during pregnancy, a period when even small biochemical disruptions may have outsized effects on fetal brain development.” 

The authors stress that no pregnant patient should discontinue or alter medication without medical supervision, as many SBIMs are essential, often life-saving treatments. Instead, the study calls for a re-evaluation of prescribing practices and for developing safer alternatives for use during pregnancy. 

Potential next steps 

The research team proposes several actions to improve drug safety for pregnant patients: 

  • Create a comprehensive list of medications with sterol-inhibiting effects. 
  • Evaluate all new pharmaceuticals for unintended sterol pathway inhibition. 
  • Increase provider education about medication-associated sterol disruption during pregnancy. 
  • Discuss safer alternatives when discontinuing treatment is not possible. 
  • Avoid prescribing multiple SBIMs for pregnant women whenever feasible. 
  • Identify patients with genetic vulnerabilities in sterol metabolism, as they might be particularly sensitive to SBIM effects. 
  • Invest in further research to understand mechanisms and mitigate risk. 

Funding: The work was conducted using the Epic Cosmos national data platform and included collaboration among UNMC’s Department of Pediatrics, Department of Biostatistics, Munroe-Meyer Institute, other UNMC departments and the Child Health Research Institute (CHRI). The study received support from UNMC/CHRI internal resources, the Dorothy B. Davis Foundation and the Nebraska Tobacco Settlement Fund. 

Key Questions Answered:

Q: Should I stop taking my antidepressants or blood pressure meds if I’m pregnant?

A: Absolutely not without medical supervision. Senior author Dr. Karoly Mirnics stresses that many of these drugs are life-saving. Stopping them abruptly can cause severe harm to both the mother and the baby. This study is a call for doctors to re-evaluate prescribing practices and look for safer alternatives, not for patients to self-medicate.

Q: Does this mean these drugs are “toxic”?

A: No. These medications are considered safe and effective for adults. The issue is specific to fetal development, a highly sensitive window where even a small disruption in cholesterol production can change how the brain’s “wiring” is formed.

Q: Why are so many more pregnant women taking these drugs now?

A: The study noted a sharp rise from 4% to nearly 17% exposure over 10 years. This reflects broader trends in managing maternal mental health and cardiovascular issues. The goal now is to identify which specific drugs in these classes don’t inhibit the sterol pathway so mothers can stay healthy safely.

Editorial Notes:

  • This article was edited by a Neuroscience News editor.
  • Journal paper reviewed in full.
  • Additional context added by our staff.

About this autism and neuropharmacology research news

Author: John Keenan
Source: 
UNMC
Contact: John Keenan – UNMC
Image: The image is credited to Neuroscience News

Original Research: Open access.
Study suggests link between prenatal exposure to certain medications and increased autism risk” by Eric S. Peeples, A. Jerrod Anzalone, Ran Dai, Elizabeth Reisher, Zeljka Korade & Karoly Mirnics. Molecular Psychiatry
DOI:10.1038/s41380-026-03610-7


Abstract

Study suggests link between prenatal exposure to certain medications and increased autism risk

Cholesterol is a vital molecule, especially during embryonic development. Disruption of the cholesterol biosynthetic pathway can arise from pathogenic genetic variants or exposure to prescription medications.

We investigated the relationship between fifteen sterol biosynthesis inhibiting medications (SBIM) prescribed during pregnancy and the incidence of autism spectrum disorders (ASD) in the resulting offspring.

Our study of the Epic Cosmos database queried linked child and maternal health records for births between 2014 and 2023 with follow-up to December 2025. The study included 6,135,213 children with linked maternal health records.

We evaluated the incidence of ASD associated with maternal prescription of aripiprazole, atorvastatin, bupropion, buspirone, fluoxetine, haloperidol, metoprolol, nebivolol, pravastatin, propranolol, rosuvastatin, sertraline, simvastatin, and/or trazodone during pregnancy using Cox proportional hazard modeling.

We found that exposure to at least one SBIM during pregnancy was associated with a 1.47-fold (95% CI 1.45–1.49) increased risk of an ASD after adjusting for potential confounders. For each additional SBIM co-prescribed, there was a 1.33 (95% CI 1.32–1.34) times increased risk of ASD, reaching 2.33-fold risk when 4 or more SBIMs were prescribed simultaneously.

In the ten years of our cohort, we identified 234,971 (3.8%) children with an ASD diagnosis. Of the children with an ASD diagnosis, 35,152 (15.0%) of the mothers were prescribed at least one SBIM during pregnancy.

Notably, in our dataset, utilization of SBIM medications by pregnant women increased from 4.6% in 2014 to16.8% in 2023. In conclusion, SBIMs may be potentially harmful to the developing fetus.

Given that these drugs account for over 400 million prescriptions annually in the U.S. we recommend these findings be considered before prescribing SBIM medications during pregnancy.